The present invention relates to a multi-composition stick product comprising a molded stick composition, such as a lip balm, sun screen deodorant, or glue stick, provided in a container which serves as the mold during manufacture and from which the composition may be advanced/ejected and retracted. The invention also relates to a process and system for manufacturing the stick product.
Lip balms, deodorants, sunscreens, and glue sticks, usually have a single homogenous color or fragrance. These products typically are aesthetically neutral or unpleasing. As a result, patients, in particular, children, often do not apply such topical products and, therefore, do not benefit from these products. For example, children often do not apply a sunscreen lip balm for protecting their lips before playing outside.
Therefore, it is desirable to develop lip balms, deodorants, sunscreens, glue sticks, and related products which are aesthetically pleasing to increase use of such products and consumer/patient compliance.
Additionally, since lip balm compositions are often the same homogenous color and fragrance, patients often cannot identify one lip balm formulation from another. For example, a patient having a lip balm with a sunscreen, e.g., paba, and another without sunscreen, needs to be able to readily distinguish the two products from one another. Similarly, it would be desirable to easily identify any specific type of lip balm, deodorant, sunscreen, glue stick, or related product.
Homogenous compositions may be manufactured using conventional techniques, such as a nozzle fill or flood fill method. In the nozzle fill method a homogeneous composition is dispensed from a filling nozzle directly into the container itself, whereas in the flood fill method the container is placed in an opening of a tray and the composition is poured onto the tray thereby flooding the tray and, in turn, filling the container. These conventional techniques, however, are not suitable for use in manufacturing a multi-composition stick product, that is, a stick product which contains two or more compositions.
Methods have been developed for use in manufacturing multi-color lipsticks that are manufactured in a mold and then removed and transferred to a separate container. In such products the composition does not contact the walls of the container in which the product is ultimately disposed. For example, U.S. Pat. No. 4,291,018 discloses a method for manufacturing a lipstick having a construction of the core-sheath type which comprises two different compositions arranged as an inner core surrounded by an outer sheath. The formation of a core-sheath type lipstick is realized using a molding body having an upper part and a lower part. A rod is inserted into the molding body and then the molten mass of the lipstick composition for the molding of the sheath is poured into the cavity and cooled to form the sheath portion around the rod. Then the rod and upper part of the molding body are removed thereby forming a core cavity. The upper part is remounted and a molten mass of the composition for the molding of the core is poured into the core cavity and cooled to solidify the composition. Thereafter, the upper part is demounted and the molded product is removed from the lower part and mounted in a suitable case to obtain a lipstick. As a finished product the lipstick does not contact the inner walls of the container.
U.S. Pat. No. 4,743,443 discloses a method for manufacturing a tri-color lipstick divided into three parallel laminae. A T-shaped centrally disposed insert is placed in a cylindrical cavity main body portion of a mold. First and third laminae are poured while maintaining a space for the later pouring of the second intermediate lamina. Thereafter, the insert is removed and the second intermediate lamina is poured. The tri-color lipstick is then removed from the mold and disposed so as not to contact the inner walls of the container.
U.S. Pat. Nos. 4,786,449 and 4,602,886 teach manufacturing a multi-color marking implement in a transparent lipstick type container that also serves as the mold during the casting process. A variegated color pattern is built up by dispensing different color compositions, dropwise, into the container. The elimination of the use of a mold between colors allows mixing at the interface between adjacent colors, thereby forming a random design. The dropwise method used to generate a random pattern is also disadvantageously slow.
It is therefore desirable to develop a multi-composition stick product in which the compositions, which preferably differ in at least one component, e.g., color, are arranged in a predetermined non-random pattern that is reproducible, and to develop a method and apparatus for manufacturing the same.
The present invention provides a multi-composition stick product comprising a container and a molded stick composition disposed so as to contact the walls of the container and be advanceable and retractable in the container. To assist in allowing the molded stick composition to freely advance and retract, the interior walls of the container are substantially smooth. The stick composition comprises a first composition and a second composition. The first and second compositions differ in at least one component, i.e., the first or second composition contains a component which is not contained in the other composition, and are arranged in a predetermined non-random pattern that is reproducible.
Also disclosed is a method for manufacturing a multi-composition stick product as described above. A mold shaft is first inserted into the container and a first composition of stick composition is dispensed into the container around the mold shaft. The mold shaft is then removed from the container to form a cavity and at least a portion of the cavity is filled with a second composition of stick composition.
In another embodiment of a method for manufacturing the multi-composition stick product in accordance with the present invention a first composition of stick composition is dispensed into the container. While the first composition is in a molten state, a mold shaft is then inserted into the container so as to displace the first composition therein. Once the first composition is sufficiently solidified, the mold shaft is removed from the container to form a cavity. Finally, at least a portion of the cavity is filled with a second stick composition.
Furthermore, the invention is directed to a system for carrying out the method described above. The system includes a filling nozzle including a mold shaft insertable into the container and an outer barrier disposed about at least a portion of the mold shaft so as to form a passageway between the outer barrier and the mold shaft for receiving the first composition.
According to a special aspect of this invention, a stick product is provided comprising a container and a molded stick composition disposed so as to contact the walls of the container and be advanceable and retractable in the container. Again, the walls of the container may be substantially smooth to facilitate the movement of the stick composition. The container confers a desired shape or design to the stick composition and the stick product. At least a portion of the outer and/or inner contour of the container is non-circular. For example, the outer and inner contours of the container may be heart shaped. Alternatively, the outer contour of the container may be heart shaped while the inner contour is circular or vice versa. In this embodiment, the stick composition may have only one phase (homogeneous) or two or more distinct phases.
An alternative embodiment of a system in accordance with the present invention for simultaneously dispensing the first and second compositions includes a first filling nozzle for dispensing the first composition and a second filling nozzle for dispensing the second composition. The first and second filling nozzles are connected together using a securing mechanism and, when assembled are capable of being inserted together into the container.